Fintech Lab
Lesson 22Advanced and capstonesAdvanced
Audit trail with structured metadata
WHO did it, WHAT triggered it, WHY, and the dedup key.

Every journal entry in a real ledger carries metadata beyond the description: WHO posted it, WHAT external event caused it, WHY (a structured reason code), and a UNIQUE dedup key so a retried webhook does not double-book. When the auditor sits down, their first question is always 'why does this entry exist?' Without metadata, your answer is 'I don't know.' Apply the steps, then switch to the Journal view (top-left toggle) to see the metadata attached to each entry.

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